Synopsis

Input Parameters

- value put in all diagonals of eliminated rows (0.0 will even eliminate diagonal entry)

x

- optional vector of solutions for zeroed rows (other entries in vector are not used)

b

- optional vector of right hand side, that will be adjusted by provided solution

Notes

This does not change the nonzero structure of the matrix, it merely zeros those entries in the matrix.

The user can set a value in the diagonal entry (or for the AIJ and
row formats can optionally remove the main diagonal entry from the
nonzero structure as well, by passing 0.0 as the final argument).

For the parallel case, all processes that share the matrix (i.e.,
those in the communicator used for matrix creation) MUST call this
routine, regardless of whether any rows being zeroed are owned by
them.

Each processor can indicate any rows in the entire matrix to be zeroed (i.e. each process does NOT have to
list only rows local to itself).